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M Ladetto

Publications and source records attributed to M Ladetto.

At least 19 recordsLinked to original sources
PubMed2006

Prolonged survival and low incidence of late toxic sequelae in advanced follicular lymphoma treated with a TBI-free autografting program: updated results of the multicenter consecutive GITMO trial.

This study provides an updated report of the consecutive multicenter Gruppo Italiano Trapianto Midollo Osseo trial employing an intensified, purging-free, total body irradiation-free, high-dose sequential chemotherapy schedule with peripheral blood stem cell autograft (i-HDS) in advanced-stage follicular lymphoma (FL). Special interest has been devoted to late toxicities and outcome in terms of molecular status. Ninety-two untreated FL patients aged <or=60 were enrolled by 20 Italian centers and evaluated on an intention-to-treat basis. Main findings are as follows: (1) 5.5-years overall survival projection of 80% (median follow-up: 68 months), with no differences related to age-adjusted IPI score; (2) 46 (50%) of 92 patients presently in continuous complete remission; (3) projected long-term progression-free survival exceeding 80% for patients collecting PCR-negative stem cell harvests or achieving molecular remission within the first 2 years from the end of therapy; (4) actuarial 5-years risk of developing secondary myelodysplasia and acute myeloid leukemia of 3.7%, with most of these events occurring in patients re-treated for recurrent lymphoma. These results demonstrate that i-HDS is feasible, effective and safe even in terms of long-term outcome. As the HDS schedule can be easily supplemented with Rituximab, it is one of the best options for random comparison with Rituximab-supplemented conventional chemotherapy.

Adolescent↗
PubMed2006

Clinical significance of cyclooxygenase-2 (COX-2) in multiple myeloma.

Several biological and clinical considerations suggest the involvement of cyclooxygenase-2 (COX-2), the key enzyme of prostaglandin (PG) synthesis, in the pathogenesis and progression of haematological malignancies. Despite the wealth of data concerning COX-2 expression, only limited information is available on multiple myeloma (MM). Using standard immunohistochemistry we therefore evaluated COX-2 protein expression in samples from 57 patients with a primary diagnosis of MM. Time to progression and a variety of clinicopathological features were evaluated by the Kaplan-Meier method and the Cox regression model. In addition, COX-2 expression was evaluated by staining bone marrow from healthy donors and 11 patients with MGUS. Overall, 31 MM samples (54%) expressed COX-2. Positivity for COX-2 was unrelated to stage or clinical or molecular features of the disease. However, patients with COX-2 positive tumours experienced a significantly shorter time to progression (17 vs 30 months, p = 0.037). In summary, COX-2 is frequently expressed in MM and correlates with shorter progression-free survival.

Adult↗
PubMed2005

Marked telomere shortening in mobilized peripheral blood progenitor cells (PBPC) following two tightly spaced high-dose chemotherapy courses with G-CSF.

The purpose of the study was to compare telomere length (TL) in peripheral blood progenitor cells (PBPC) collected after two tightly spaced high-dose (hd) chemotherapy courses. We assessed 37 previously untreated lymphoma patients undergoing a hd-chemotherapy program with autografting. They sequentially received hd-cyclophosphamide (CY) and hd-Ara-C, both followed by PBPC harvesting. Both post-CY and post-Ara-C harvests were assessed for TL by Southern blot analysis. In 12 patients, the assay was also performed on purified CD34+ cells. All patients displayed high PBPC mobilization following both hd-CY and hd-Ara-C. In all but one patient, TL was shorter in PBPC collected after Ara-C compared to CY: 7226bp (range: 4135-9852) vs 8282 bp (range 4895-14860) (P < 0.0001). This result was confirmed on CD34+ cells. Platelet recovery in patients receiving post-Ara-C PBPC was significantly slower compared to those receiving post-CY PBPC. In conclusion, (i) administration of tightly spaced hd-chemotherapy courses induces marked telomere shortening on harvested PBPC; (ii) engraftment kinetics seem slower, with delayed platelet recovery, in patients autografted with PBPC suffering marked TL erosion; (iii) long-term follow-up is required to verify whether PBPC with shortened telomeres display defective engraftment stability and/or risk of secondary leukemia; (iv) TL evaluation is advisable whenever new mobilization procedures are developed.

Adolescent↗
PubMed2003

Detection of minimal residual disease by real-time PCR can be used as a surrogate marker to evaluate the graft-versus-myeloma effect after allogeneic stem cell transplantation.

Allogeneic stem cell transplantation (allo-SCT) is an effective and potentially curative treatment for some cases of multiple myeloma (MM). The curative efficacy of allo-SCT may be largely attributed to its immunological activity, the graft-versus-myeloma (GVM) effect. To evaluate the kinetics of residual myeloma cells, we analyzed the follow-up bone marrow samples of three MM patients by means of a real-time molecular assay. We identified a consistent correlation between onset of graft-versus-host disease and disease response. These data suggest that real-time molecular follow-up can be used to monitor the GVM effect and that it can be employed in the clinical setting to tailor post transplant immunomodulation.

Adult↗
PubMed2001

A validated real-time quantitative PCR approach shows a correlation between tumor burden and successful ex vivo purging in follicular lymphoma patients.

OBJECTIVE: Purging procedures are increasingly used to provide stem cell collections devoid of contaminating tumor cells. In follicle center lymphoma (FCL), most approaches eradicate polymerase chain reaction (PCR);-detectable disease in only a fraction of harvests undergoing ex vivo manipulation. In this study we evaluated whether there is a relationship between tumor burden of stem cell harvests and successful clearance of PCR-detectable disease following ex vivo manipulation. MATERIALS AND METHODS: To address this issue, we developed a real-time PCR approach for quantitative measurement of tumor contamination using the bcl-2 rearrangement. Real-time PCR was used to evaluate the relationship between tumor burden of stem-cell harvests and purging effectiveness in PCR(+) samples derived from 10 FCL patients. Ex vivo purging was performed using the MaxSep cell separator (Baxter Immunotherapy, Deerfield, IL, USA). RESULTS: Our real-time PCR method proved effective, sensitive, accurate, and reproducible. Four collections were successfully cleared of minimal residual disease (MRD) whereas six remained PCR(+). Real-time PCR showed that the four collections successfully cleared of MRD had a prepurging tumor burden significantly lower than those remaining PCR(+) (p = 0.04). CONCLUSION: This study provides the first evidence that evaluation of tumor burden in stem-cell harvests by real-time PCR can predict the effectiveness of therapeutic intervention in non-Hodgkin's lymphoma. Based on these findings, we foresee a more widespread use of this technique to evaluate the impact of different therapeutic approaches in FCL.

Adolescent↗
PubMed2001

High-dose mitoxantrone + melphalan (MITO/L-PAM) as conditioning regimen supported by peripheral blood progenitor cell (PBPC) autograft in 113 lymphoma patients: high tolerability with reversible cardiotoxicity.

Hematological and extrahematological toxicity of high-dose (hd) mitoxantrone (MITO) and melphalan (L-PAM) as conditioning regimen prior to peripheral blood progenitor cell (PBPC) autograft was evaluated in 113 lymphoma patients (87 at disease onset). Autograft was the final part of a hd-sequential (HDS) chemotherapy program, including a debulkying phase (1-2 APO +/- 2 DHAP courses) and then sequential administration of hd-cyclophosphamide, methotrexate (or Ara-C) and etoposide, at 10 to 30 day intervals. Autograft phase included: (1) hd-MITO, given at 60 mg/m2 on day -5; (2) hd-L-PAM, given at 180 mg/m2 on day -2; (3) PBPC autograft, with a median of 11 x 10(6) CD34+/kg, or 70 x 10(4) CFU-GM/kg, on day 0. A rapid hematological recovery was observed in most patients, with ANC >500/microL and Plt >20,000/microl values reached at a median of 11 and 10 days since autograft, respectively. The good hemopoietic reconstitution allowed the delivery of consolidation radiotherapy (RT) to bulky sites in 53 out of 57 candidate patients, within 1 to 3 months following autograft; five of these patients required back-up PBPC re-infusion due to severe post-RT pancytopenia. Few severe infectious complications were recorded. There was one single fatal event due to severe pancytopenia following whole abdomen RT. Cardiac toxicity was evaluated as left ventricular ejection fraction (LVEF), monitored by cardiac radionuclide scan. LVEF prior to and after autograft was significantly reduced (median values: 55% vs 46%) in 58 evaluated patients; however, a significant increase to a median value of 50% was observed in 45 patients evaluated at 1 to 3 years since autograft. At a median follow-up of 3.6 years, 92 patients are alive, with a 7-year overall survival projection and 6.7-year failure-free survival projection of 77% and 69%, respectively. We conclude that a conditioning regimen with hd-MITOIL-PAM fits well within the HDS program. It implies good tolerability and reversible cardiotoxicity and it may have contributed to the good long-term outcome observed in this series of patients.

Adolescent↗
PubMed2001

Concurrent administration of high-dose chemotherapy and rituximab is a feasible and effective chemo/immunotherapy for patients with high-risk non-Hodgkin's lymphoma.

The aim of this study was to investigate feasibility, tolerability and efficacy of rituximab-supplemented high-dose sequential chemotherapy (R-HDS) with peripheral blood progenitor cell autografting as frontline or salvage treatment in patients with advanced non-Hodgkin's lymphoma (NHL). Thirty-two patients have been treated: 14 at disease onset and 18 with relapsed or progressive disease. R-HDS regimens included six courses of rituximab. Rituximab was delivered either concurrently with high-dose chemotherapy to exploit the in vivo purging properties of the drug as well as at the end of the treatment plan to target minimal residual disease. All patients treated at disease onset completed their treatment with no life-threatening toxicity, while two toxic deaths due to severe bilateral pneumonia were observed among patients treated due to relapsed or refractory disease. Thirteen of 14 patients treated up-front achieved CR. Among pre-treated patients 10 of 18 achieved CR with better results in patients with relapsed (seven of eight) compared to progressive disease (three of 10). PCR analysis was carried out in indolent lymphoma patients: nine of nine follicular lymphomas and three of six CD5-positive NHL collected PCR-negative peripheral blood progenitor cell harvests. The results of this pilot study show that R-HDS is feasible and effective with acceptable toxicity when used at disease onset. In pre-treated patients this treatment also showed promising results, although the risk of severe infections needs to be considered.

Adult↗
PubMed2001

Central nervous system relapse in a patient with mantle cell lymphoma in continuous clinical and molecular remission at six years since autografting.

Although molecular remissions have been frequently observed and associated with low likelihood of relapse in some lymphoid tumours, they are seldom reported in mantle cell lymphoma (MCL). We performed PCR analysis of a MCL patient with central nervous system (CNS) relapse occurring 76 months after autologous transplantation. Molecular follow-up showed constant absence of PCR-detectable disease, even after the onset of relapse. These data indicate that isolated CNS relapse may occur even after several years of continuous remission and cannot be excluded based on a persistent pattern of molecular remission. However, the prolonged remission duration observed in this patient suggests that achieving PCR-negativity may also be of benefit for MCL patients.

Central Nervous System Neoplasms↗
PubMed2000

Immunoglobulin heavy-chain consensus probes for real-time PCR quantification of residual disease in acute lymphoblastic leukemia.

Tumor-related immunoglobulin heavy-chain (IgH) rearrangements are markers for polymerase chain reaction (PCR) detection of minimal residual disease (MRD) in B-cell malignancies. Nested PCR with patient IgH allele-specific oligonucleotide primers can detect 1 tumor cell in 10(4) to 10(6) normal cells. In childhood acute lymphoblastic leukemia (ALL), persistence of PCR-detectable disease is associated with increased risk of relapse. The clinical significance of qualitative PCR data can be limited, however, because patients can harbor detectable MRD for prolonged periods without relapse. Recent studies indicate that a quantitative rise in tumor burden identifies patients who are at high risk for relapse. Therefore, an efficient and reliable PCR method for MRD quantification is needed for ALL patients. We have developed a real-time PCR method to quantify MRD with IgH V(H) gene family consensus fluorogenically labeled probes. With this method, a small number of probes can be used to quantify MRD in a large number of different patients. The assay was found to be both accurate and reproducible over a wide range and capable of detecting approximately 1 tumor cell in 5 x 10(4) normal cells. We demonstrate that this methodology can discriminate between patients with persistence of MRD who relapse and those who do not. This technique is generally applicable to B-cell malignancies and is currently being used to quantify MRD in a number of prospective clinical studies at our institution. (Blood. 2000;95:2651-2658)

Base Sequence↗
PubMed2000

Rituximab anti-CD20 monoclonal antibody induces marked but transient reductions of peripheral blood lymphocytes in chronic lymphocytic leukaemia patients.

Rituximab has been recently proposed as an effective non-chemotherapeutic option for patients with follicle centre lymphoma (FCL). However, less is known on its role in chronic lymphocytic leukaemia (CLL). We thus decided to assess its effectiveness on a panel of 7 patients with refractory or relapsed CLL. Mild (5 patients) or severe (1 patient) adverse reactions were observed during the first hours of Rituximab infusion, almost exclusively at the first course. Symptoms rapidly subsided with temporary drug withdrawal and low dose steroids. All patients could receive the whole scheduled treatment. A striking reduction of peripheral blood (PB) lymphocyte counts was observed in all patients (median 93%; range 57-99%). However, Rituximab was poorly effective towards nodal and splenic disease. Patients required additional treatment after a median time of 70 d (range: 20-180 d). Our data show that Rituximab delivery in CLL patients is feasible and has an acceptable toxicity, although it probably does not represent an ideal treatment option when delivered using schedules originally designed for FCL patients. However, responses observed at PB level suggest that Rituximab has an activity which is not negligible and deserves further investigation in CLL. Future approaches will be directed to the development of alternative schedules which may include dose intensification, combination of Rituximab and chemotherapy, and in vivo purging of peripheral blood progenitor cell harvests for autografting procedures.

Aged↗
PubMed2000

Real-Time polymerase chain reaction of immunoglobulin rearrangements for quantitative evaluation of minimal residual disease in multiple myeloma.

The majority of patients with multiple myeloma (MM) have persistence of minimal residual disease (MRD), as determined by polymerase chain reaction (PCR) detection of clonal immunoglobulin H (IgH) gene rearrangements. As a result, PCR analysis has not provided clinically useful prognostic information in myeloma patients. Instead, quantitative PCR approaches are required to predict patient outcomes and assess response to novel treatment strategies. We adapted real-time PCR technology to quantify myeloma cells using the IgH rearrangement and then assessed the utility of this approach in 29 patients with myeloma who had undergone autologous stem cell transplantation. Because of the high cost of producing a specific reporting probe for each patient, H-chain V-region family-specific consensus probes were used in association with allele-specific oligonucleotides for PCR amplification. Because of the high frequency with which somatic hypermutation at the immunoglobulin locus occurs in MM, a number of mismatches occurred between the patient sequences and the consensus probe. However, construction of a limited number of probes allowed real-time PCR with a sensitivity of 10(-4) to 10(-5). To validate this method, we extensively evaluated assay accuracy and reproducibility. Results indicate that real-time PCR using consensus probes provides a feasible, accurate, and reproducible method for evaluating MRD in M M and possibly in other differentiated B-cell malignancies, and one that is less expensive than the use of patient-specific probes. This technique is being used to assess tumor depletion after immunologic purging and changes in tumor burden in patients undergoing stem cell transplantation and novel treatment approaches.

Gene Rearrangement, B-Lymphocyte, Heavy Chain↗
PubMed2000

Immunoglobulin framework-derived peptides function as cytotoxic T-cell epitopes commonly expressed in B-cell malignancies.

Although the idiotypic structures of immunoglobulin from malignant B cells were the first tumor-specific determinants recognized, and clinical vaccination trials have demonstrated induction of tumor-specific immunity, the function of immunoglobulin-specific CD8+ cytotoxic T lymphocytes in tumor rejection remains elusive. Here, we combined bioinformatics and a T cell-expansion system to identify human immunoglobulin-derived peptides capable of inducing cytotoxic T-lymphocyte responses. Immunogenic peptides were derived from framework regions of the variable regions of the immunoglobulin that were shared among patients. Human-leukocyte-antigen-matched and autologous cytotoxic T lymphocytes specific for these peptides killed primary malignant B cells, demonstrating that malignant B cells are capable of processing and presenting such peptides. Targeting shared peptides to induce T-cell responses might further improve current vaccination strategies in B-cell malignancies.

B-Lymphocytes↗
PubMed2000

Long-term follow-up of advanced-stage low-grade lymphoma patients treated upfront with high-dose sequential chemotherapy and autograft.

Long-term outcome, after first line intensified high-dose sequential (i-HDS) chemotherapy, was evaluated in 46 patients, aged < or =65 years, with advanced low-grade lymphoma. Seventeen patients had small lymphocytic lymphoma (SLL), 29 had follicular lymphoma (FL), 10 of them with histologic transformation. I-HDS included: (1) tumor debulking, by 2 APO+2 DHAP courses; (2) sequential administration of high-dose (hd) etoposide, methotrexate, and cyclophosphamide, followed by peripheral blood progenitor cell (PBPC) harvest; (3) hd-mitoxantrone + melphalan with PBPC autograft. Ten FL patients had their PBPC immunologically purged ex vivo. There were two treatment-related deaths; five FL patients had short-lasting response followed by disease progression, five SLL reached a stable PR; overall, 34 patients (74%) reached CR. At a median follow-up of 4.3 years, the estimated 9-year OS and EFS were 84% and 45%, respectively. No significant differences were observed in the OS among patients at low, intermediate or high IPI score, with an estimated OS projection of 95%, 78%, and 75%, respectively. FL had longer survival without evidence of residual disease (9-year EFS: 59%) as compared to SLL patients (8.8-year EFS: 17%); however, both groups had prolonged survival and no need of salvage treatment, as shown by the time to disease progression curve, projected to 66% and 62% for SLL and FL, respectively. The results indicate that hd-approach in low-grade lymphoma: (1) is associated with longer progression-free survival as compared to conventional therapies; (2) may imply higher tumor mass reduction in FL as compared to SLL patients; (3) offers long life expectancy, with potential survival benefits at least for patients at intermediate/high IPI score.

Adult↗
PubMed1999

Negative immunomagnetic ex vivo purging combined with high-dose chemotherapy with peripheral blood progenitor cell autograft in follicular lymphoma patients: evidence for long-term clinical and molecular remissions.

The feasibility and efficacy of a novel immunomagnetic ex vivo negative purging method was evaluated on peripheral blood progenitor cells (PBPC) from 13 non-Hodgkin's lymphoma patients (eight follicular, FL; three mantle cell, MCL; two FL with histologic transformation). A peculiar feature of the study was the collection of PBPC after prolonged tumor debulking. Our method included a stem cell enrichment phase followed by cell incubation with anti-B cell MoAbs (anti-CD19, CD20, CD22, CD23), addition of immunobeads, and then positive cell removal by passage on a Max-Sep (Baxter Immunotherapy) cell separator. Engraftment was rapid and stable. Hematological values were assessed 1 and 2 years after the autograft. Purging efficacy was molecularly assessed in a panel of 11 patients who showed persistence of PCR-detectable lymphoma cells on PBPC harvests despite intensified chemotherapeutic debulking. PCR-negativity was obtained in vitro and persisted in vivo after autograft in three FL patients; five more FL patients, whose purged PBPC were PCR+, converted to stable (3 patients) or fluctuating (two patients) PCR negativity after autograft. MCL patients never reached PCR negativity. Thus, ex vivo purging may have a role for FL patients harvesting PCR-positive PBPC after intensified chemotherapy. In contrast, the addition of ex vivo purging seems to be of little if any benefit for MCL patients.

Adult↗
PubMed1999

Clinical relevance of minimal residual disease monitoring in non-Hodgkin's lymphomas: a critical reappraisal of molecular strategies.

Although current treatments can induce clinical complete remissions in the vast majority of patients with indolent lymphoma, most of them actually relapse, because of the persistence of residual tumor cells which are undetectable using conventional diagnostic procedures. Polymerase chain reaction (PCR)-based methods are increasingly used for minimal residual disease detection (MRD), and provide useful prognostic information. In this review, current approaches for MRD detection in indolent lymphomas are summarized. In addition, the prognostic aspects of molecular monitoring after transplantation procedures are discussed. The experience accumulated over the past decade shows that PCR analysis has a prognostic impact in several therapeutic programs including conventional and high-dose regimens. Major advantages coming from the introduction of molecular monitoring in clinical programs have been: (1) a rapid evaluation of the anti-tumor activity of innovative treatments; and (2) an early identification of patients with a high-risk of disease recurrence.

Biomarkers, Tumor↗
PubMed1999

Molecular and clinical remissions in multiple myeloma: role of autologous and allogeneic transplantation of hematopoietic cells.

PURPOSE: To describe molecular monitoring of minimal residual disease in patients with myeloma who have achieved complete remission (CR) after autologous or allogeneic transplantation of hematopoietic cells. MATERIALS AND METHODS: Clonal markers based upon the rearrangement of immunoglobulin heavy-chain genes were generated for each patient and used for polymerase chain reaction (PCR) detection of residual myeloma cells. Fifty-one patients entered the program and 36 achieved CR. After transplantation, molecular monitoring was performed on 29 patients (15 autologous and 14 allogeneic transplants) who had molecular markers. RESULTS: Our data show that molecular remissions are rarely achieved (7%) with high-dose chemotherapy followed by single or double autografting. In addition, virtually all peripheral blood progenitor cell and bone marrow samples contained residual myeloma cells, even when sample collection was scheduled after repeated courses of high-dose chemotherapy. All patients autografted with PCR-positive cells remain positive, and eight of 15 have relapsed. Two patients were autografted with PCR-negative cells: one is in clinical and molecular remission, and one relapsed 25 months after the transplant. In the allografting setting, a higher proportion of patients (50%) achieved molecular remission; there were two relapses, one in the PCR-positive group and one in the PCR-negative group. CONCLUSION: This is the first large study of molecular remissions in myeloma patients to use a PCR-based approach utilizing patient-specific tumor markers. The sizeable fraction of patients who achieved molecular remission after allografting with peripheral blood progenitor cells represents a promising finding in an incurable disease.

Adult↗